Neon tube by-pass



Patented. Get. 25, 1932 UNITED STATES PATENT ()FFICE RUIBERT E. MCCOMBES, DECEASED, LATE OF BUFFALO, NEW YORK, BY ESTHER W. MCCGMBES, ADMINISTRATRIX, F BUFFALO, NEW YORK NEON TUBE BY-PASS Application filed June 24, 1931. Serial No. 546,608.

vision of a neon tube by-pass of the above stated character which will be simple, durable and efiicient and which may be manufactured and sold at a comparatively low cost.

With these and other objects in view, this invention consists in certain novel features of construction, combination and arrangement of parts to be hereinafter more fully described and claimed.

For a complete understanding of his invention, reference is to be had to the following description and accompanying drawing, in which Figure 1 is a diagrammatical view illustrating a by-pass for each of the neon tubes 5 of a series and constructed in accordance with his invention.

Figure 2 is a sectional view drawn on an enlarged scale illustrating the by-pass.

Figure 3 is a top plan view illustrating the same.

Figure 4 is a sectional view taken on the line H of Figure 2.

Figure 5 is a similar view taken on the line 5--5 of Figure 2.

Figure 0 inent,

Referring in detail to the drawing, the numeral 1 indicates a plurality of neon tubes connected in series by conductors 2 with a of the tubes becoming defective or burnt out ,I

renders the remaining tubes inoperative consequently destroymg the device for further use until the defect is located and which is dificult when all of the tubes are extinso guished and to render the detection of the is a fragmentary sectional view illustrating a modified form of fusible ele-' defective tube easy and also permit the other tubes of the series to be restored to operation should one of the tubes burn out or become defective, his invention is employed and consists of a bypass element 5. A bypass element is provided for each of the tubes and is electrically connected parallel with the respective tube by conductors 6.

The by-pass element 5 includes an insulated body 7 having oppositely disposed chambers 8 closed by removable caps 9 of insulated material. Stationary contacts 10 are electrically connected by a conductor strip 11 embedded in the body 7 with the contacts arranged in the outer ends of the chambers 8. Spring pressed plungers or movable contacts 12 are slidably mounted in the chambers 8 and adapted to be urged into engagement with the stationary contacts by expan sion springs 13. The movable contacts or plungers l2 carry terminal posts 14 that extend through openings 15 of the body 7 and have terminals 16 removably secured thereto and to which the conductors 6 are secured.

The opposing ends of the terminals 16 are bent to form hooks 17 to be engaged by a non-conductive fusible element 18 adapted to retain the plungers 12 in a retracted position or disengaged from the contacts 10. The posts 14 and terminals 16 when in the last named position form an air gap between the posts, so that during the normal operation of the tubesythe by-pass circuits will be broken and should one of the tubes become burnt out or defective so as to render the same inoperative, the voltage of the electrical current is consequently increased in the series and will jump the air gap fusing or destroying the element 18 permitting the plungers 12 to engage the contacts 10 restoring the electric circuit to the other tubes and eliminating from said circuit the defective tube. It is to be understood that the byass element is placed in parallel with each 0 the tubes so that should any one of the tubes become defective/or the respective circuit thereof, the respective by-pass element Wlll function to restore the circuit to the other tubes. The restoring of the circuit to the other tubes and cutting out of the defective having said protection is obvious, that is, any

arcing anywhere in the electric circuit of the tube will create a sympathetic arcing at the next weakest point and the trouble becomes cumulative. The by-passes will be automatically operated by the arcing above referred to or in case of a tube becoming inoperative or defective and also will become operative in case of a broken connection between the tubes and their respective Wires.

The fusible element 18 may be constructed from shellacked cotton or silk threads or horsehair and as shown in Figure 6 a pair of fusible elements 18 are connected together by an insulating block 19 and applied to the hooks 17 of the terminals 16 to hold the plungers retracted breaking the circuit and forming the desired air gap. This gap should be approximately of an inch or may be increased and decreased as to size by lengthening or shortening the fusible element.

\Vhile he has shown and described the preferred embodiment of his invention, it will be understood that minor changes in construction, combination and arrangement of parts may be made without departing from the spirit and scope of his invention, as claimed.

Having thus described his invention, what he claims is:

1. A by-pass element comprising an insulated body having opposed chambers, removable caps carried by the body for closing the chambers, electrically connected stationary contacts in said chambers, spring pressed movable plungers to engage the stationary contacts, posts carried by the plungers, terminals carried by the posts and connected in an electrical circuit, hooks on said terminals, and a fusible means connecting the hooks to disengage the plungers from the contacts and providing an air gap between the posts to break the circuit until the voltage of the electricity of said circuit increases sufficiently to ump the gap and destroy the fusible means for freeing the plungers to engage the stationary contacts and complete the circuit between the posts.

2. A by-pass element comprising an insulated body having chambers, electrically con nected stationary contacts in said chambers, spring pressed movable plungers in said 7 V chambers to engage the contacts when freed,

posts carried by the plungers and connected in an electric circuit, and a fusible element connecting the posts to maintain the plungers out of engagement with said contacts and providing an air gap between the posts to break the circuit until the voltage of the electricity of said circuit increases sufficiently to jump the gap and destroy the fusible element, thereby freeing the plungers to enloo 

